[U-Boot] [PATCH v2 5/5] x86: Switch to using generic global_data setup

[Simon Glass]

There is quite a bit of assembler code that can be removed if we use the
generic global_data setup. Less arch-specific code makes it easier to add
new features and maintain the start-up code.

Drop the unneeded code and adjust the hooks in board_f.c to cope.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v2:
- Don't rely on value of %edx from board_init_f_mem()

 arch/x86/cpu/cpu.c   |  4 ++-
 arch/x86/cpu/start.S | 95 +++++++---------------------------------------------
 common/board_f.c     |  3 +-
 3 files changed, 18 insertions(+), 84 deletions(-)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index 4f57145..1b76ca1 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -136,8 +136,10 @@ static void load_gdt(const u64 *boot_gdt, u16 num_entries)
 	asm volatile("lgdtl %0\n" : : "m" (gdt));
 }
 
-void setup_gdt(gd_t *new_gd, u64 *gdt_addr)
+void arch_setup_gd(gd_t *new_gd)
 {
+	u64 *gdt_addr;
+
 	gdt_addr = new_gd->arch.gdt;
 
 	/* CS: code, read/execute, 4 GB, base 0 */
diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index 313fa3f..e94ddc4 100644
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -104,8 +104,7 @@ car_init_ret:
 	 *
 	 * top-> CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE
 	 *	MRC area
-	 *	global_data
-	 *	x86 global descriptor table
+	 *	global_data with x86 global descriptor table
 	 *	early malloc area
 	 *	stack
 	 * bottom-> CONFIG_SYS_CAR_ADDR
@@ -120,13 +119,10 @@ car_init_ret:
 	 * and esi holds the HOB list address returned by the FSP.
 	 */
 #endif
-
-	/* Reserve space on stack for global data */
-	subl	$GENERATED_GBL_DATA_SIZE, %esp
-
-	/* Align global data to 16-byte boundary */
-	andl	$0xfffffff0, %esp
-	post_code(POST_START_STACK)
+	/* Set up global data */
+	mov	%esp, %eax
+	call	board_init_f_mem
+	mov	%eax, %esp
 
 	/*
 	 * Debug UART is available here although it may not be plumbed out
@@ -137,56 +133,21 @@ car_init_ret:
 	 * call  printch
 	 */
 
-	/* Zero the global data since it won't happen later */
-	xorl	%eax, %eax
-	movl	$GENERATED_GBL_DATA_SIZE, %ecx
-	movl	%esp, %edi
-	rep	stosb
-
+	/* Get address of global_data */
+	mov	%fs:0, %edx
 #ifdef CONFIG_HAVE_FSP
+	/* Store the HOB list if we have one */
 	test	%esi, %esi
 	jz	skip_hob
-
-	/* Store HOB list */
-	movl	%esp, %edx
-	addl	$GD_HOB_LIST, %edx
-	movl	%esi, (%edx)
+	movl	%esi, GD_HOB_LIST(%edx)
 
 skip_hob:
 #else
 	/* Store table pointer */
-	movl	%esp, %edx
-	addl	$GD_TABLE, %edx
-	movl	%esi, (%edx)
+	movl	%esi, GD_TABLE(%edx)
 #endif
-
-	/* Setup first parameter to setup_gdt, pointer to global_data */
-	movl	%esp, %eax
-
-	/* Reserve space for global descriptor table */
-	subl	$X86_GDT_SIZE, %esp
-
-	/* Align temporary global descriptor table to 16-byte boundary */
-	andl	$0xfffffff0, %esp
-	movl	%esp, %ecx
-
-#if defined(CONFIG_SYS_MALLOC_F_LEN)
-	/* Set up the pre-relocation malloc pool */
-	subl	$CONFIG_SYS_MALLOC_F_LEN, %esp
-	movl	%eax, %edx
-	addl	$GD_MALLOC_BASE, %edx
-	movl	%esp, (%edx)
-#endif
-	/* Store BIST into global_data */
-	movl	%eax, %edx
-	addl	$GD_BIST, %edx
-	movl	%ebp, (%edx)
-
-	/* Set second parameter to setup_gdt() */
-	movl	%ecx, %edx
-
-	/* Setup global descriptor table so gd->xyz works */
-	call	setup_gdt
+	/* Store BIST */
+	movl	%ebp, GD_BIST(%edx)
 
 	/* Set parameter to board_init_f() to boot flags */
 	post_code(POST_START_DONE)
@@ -213,37 +174,7 @@ board_init_f_r_trampoline:
 	/* Stack grows down from top of SDRAM */
 	movl	%eax, %esp
 
-	/* Reserve space on stack for global data */
-	subl	$GENERATED_GBL_DATA_SIZE, %esp
-
-	/* Align global data to 16-byte boundary */
-	andl	$0xfffffff0, %esp
-
-	/* Setup first parameter to memcpy() and setup_gdt() */
-	movl	%esp, %eax
-
-	/* Setup second parameter to memcpy() */
-	fs movl 0, %edx
-
-	/* Set third parameter to memcpy() */
-	movl	$GENERATED_GBL_DATA_SIZE, %ecx
-
-	/* Copy global data from CAR to SDRAM stack */
-	call	memcpy
-
-	/* Reserve space for global descriptor table */
-	subl	$X86_GDT_SIZE, %esp
-
-	/* Align global descriptor table to 16-byte boundary */
-	andl	$0xfffffff0, %esp
-
-	/* Set second parameter to setup_gdt() */
-	movl	%esp, %edx
-
-	/* Setup global descriptor table so gd->xyz works */
-	call	setup_gdt
-
-	/* Set if we need to disable CAR */
+	/* See if we need to disable CAR */
 .weak	car_uninit
 	movl	$car_uninit, %eax
 	cmpl	$0, %eax
diff --git a/common/board_f.c b/common/board_f.c
index 37b7bf5..c959774 100644
--- a/common/board_f.c
+++ b/common/board_f.c
@@ -715,6 +715,7 @@ static int jump_to_copy(void)
 	 * with the stack in SDRAM and Global Data in temporary memory
 	 * (CPU cache)
 	 */
+	arch_setup_gd(gd->new_gd);
 	board_init_f_r_trampoline(gd->start_addr_sp);
 #else
 	relocate_code(gd->start_addr_sp, gd->new_gd, gd->relocaddr);
@@ -1033,6 +1034,7 @@ __weak void arch_setup_gd(struct global_data *gd_ptr)
 {
 	gd = gd_ptr;
 }
+#endif /* !CONFIG_X86 */
 
 ulong board_init_f_mem(ulong top)
 {
@@ -1054,4 +1056,3 @@ ulong board_init_f_mem(ulong top)
 
 	return top;
 }
-#endif /* !CONFIG_X86 */
-- 
2.5.0.rc2.392.g76e840b